Magnetic detector.



J. MURGAS. MAGNETIC DETECTOR. APPLI'OATION ILBD MAB.. 7,499?,

@mma Aug. 10, 1909.

@Hom/emp retenir ernten lfiURGi/LS, 0F WILKES-BARRE, PENNSYLVANIA.

ernennrrc marmeren.

ne. ssdv'ec.

tpecieation of Letters Patent.

Patentedeug. 1o, 190s.

Application site ramon rf, 190e, seria.; No. 483,964.

c/Z wiom it muy concern:

it known that l', Josemi Musees, a citirien of the Uni States, and resident of tiikes-'iir-ure, in the of Luzerne and Stanze ci" iennsylvsnia, have invented certain new and useful improvements in', Magnetic Detectan i which the following is a speciivcntioi'i relates to detectors for eiec- 1 l0 trieoscillations such are produced in Wire- Scria No.

less,i tsi'egraphjv, and more particularly, to detecte oi the ii'iagnetic type.

y fr detector of this character is shown-end described in n'iy copending application 455,335, filed September 29, 1908, aliowcd January 29, 1909. is explained in seid apniication, such devices depend for their o; ation upon the principle that the i'ijfste, s ot iron, or other magnetic ni aterial 1s actie" d to a marked degree by theaction said inovingonias the i'ield, the

si wi-tt 5b denser is re electric oscillations thereon. if e magnetic n hc cordinuously moved in a Ina@- 'V he continimusl)T dlsoi the magnetization ie inagnctizing force. its ione; as the magnetic nlnss is moved at a uniform rate in a 'held ci' constant strength the dishirtion renuiins the saine, hut if, noiv 'electric oscillaf due to the .lag

1 ons be caused to upon s, there is produced n sudden change in the amount of lag, and conse- `duentlj, a suiftden shifting of the magnetic itieid. Therefore, hy arranging suiteble ap paratus to indicate this sudden shifting ol' presence of such electric oscillations may' he reei'lilltr detected. Such magnetic detectors src designed to cot'rpcratc with ti'ic l serial nnd'ground wire oi a rew ceving sistion, and :irc ordinariiv connected a transforuwr or autotransformer which is preicrnhly idjustable. .ln order to facilitate propri' tuning, :in :n-ijustablc con denso so ist, herotoli heen used, the ciriaiining' the indiwtance and capacity constituting ai resonahir, which may be ndiusted s :iste respond to various oscillation freriue s, as is Well understood.

@ne oiiiect cl' the present invention is to provide a devicer which shall be more efficient anifhc'spoide oi'sherper tuning than those heretofore cmp o ved. i

It. further ohjcct is to provide e device combining the functions of detecto and condenser, in such manner that no external coni'uircd.

i i i! i i l l i i i i i/Vitli the above and other objects in View, i

and to simplify and generally improve such apparatus, my invention consists in the construction and arrangement of parts hereinafter describcd,and illustrated in the 'accompanying drawing, in whichr Figure 1 is a central section of my improved device, coinplete, parts being shown in elevation-5 Fig. 21is aperspective View, on a smaller scale, of one of the parts of the device; an d, F ig. 3 is a. diagranunatic View showing the electrical ,connections emp o ved. i i

As shown in the drawing, the magnetic eld is produced by Ineens of a pair of permarient horse shoe magnets 1, 2, arranged in Opposition, with their like poles adjacent. Other l'orins of steel `magnets or electromagnets may, of course, be equally woll einployed, if desired, the only requirement be ing` that the field produced shall be substantially constant in force and direction. Mounted between the opposed poles ci these magnets is a disk 3 preierably l'ornied ol' soit iron. This disk is mounted. on a shaft 4, and is clamped in position thereon by means oi' a nut 5, co` pe11ting with an annular siunddcr on the shaft. The sha'l't 4; ournalcd at its ends in 'fixed supports 6 and 7, one end ol' the shaft projecting beyond the support, as shown at 8. A Contact spring 9, secured at one end to the support 7, extended Aend ol'ithe shaft, and its tension is regulated by moans oi' e thund) screw 1i). pulley 11 is lixcd to the shalt and is adapted to receive a holt (not shown) hy ineens ol' which the shaft and disk may he rotntcd'.

Csiuiniortcd between the poles ol' the insg* not is a rectai-lgular l'rannc 12 having one side open, and formed oi' hard rubber or other insulating material. This l'riune is oi' a thickness slightly greater than that ol the disk, and is so disposed as to lic in the same plane. To each side of this traine is secured e thin plate ol' mica or other insulating inat'erial, es shown at 13 and 1.4-, said plates be ing provided with t central opening 15 adapted to receive th associated clamping nut 5, as shown in Fig. 1. Around the frame 1.2 and outside ol' the plates 13 and 14, is Wound a thin flat coil 1.6 ol` insulated copper Wre, which muy consist ol' one or more layersfi' This coil is, ol' course, spread apart et its middle so` as to avoid contact with the hub of the dislfhut otherwise hears swainst the b the coil is arranged so as to, as nearly as possible, envelop the disk on all sides. rlhe frame 12 is provided at its corners with projecting lugs 12, by means of which it is secured to a supporting Vframe i8, which Vframe 12E also carries binding posts 17, adapted to receive the ends of the coil 16.

Referring new to Fig. 3, it will be seen that the t-vvo terminals 19 and 2() of the coil 16, are connected to s ne electro-responsive device as a telephone receiver, 21.

23 designates the usual anto-transforiner, to which is connected the 'aerial 25 and theI ground wire 26. '.lhe points of com'iection, (lj and D, respectively, of these two wires with tlic auto-transformcr are preferably adjustable. Sonie point in the coil 16 is also connected to a point A of the auto-transformer, and for convenience, there is illustrated a conductor 22 extending from the point A to one end of the coil 16 and forming therewith a common junction With the terminal 1.9 thereof. lt will, ol` course, be understood, however, that any other part of the coil 1G may bc connected to the transformer, if dcsired, without in any way altering" the results.

Extending; from the Contact springl Q to seine point B of thc auto-transformer, is a. conductor 24, which thus serves to connect the metal of the disk 8 with the trans- 'foi-incr, The points A and B, of connection of the wires 22 and 24, respectively, are made adjustable so that any desired amount oi' inductance may be included between them.

lt will now be seen that the disk 3 and coil 16 constitute the two plates of a condenser, such `plates being separated by a suitable dielectric, such as the mica plates 13 and il. lt will also be observed that the parts 22, 23, 24, 3 and 1G, constitute a resonator, including a condenser and an adjustable inductance. ly moving the points of connection A and B closer together or farther apart, any desired tuning may be obtained, as is well understood.

In operation, the disk 3 is caused to rotate continuously at an uniform speed. As explained above, the magnetic field will be thus continuouslyT distorted, but, since the disk is of symmetrical form relative to its axis of' rotation, and since it is driven at uniform speed, the distortion of the field will remain constant', and no effect Will be produced in the vtelephone receiver. W hen, however, electric oscillations are set up i'n the resonator circuit, above described, such oscillations passing into and through the disk 3 serve to produce a sudden variation in its hysteresis, and a conse uent sudden shitting of the magnetic eld re ative to the stationary coil 16. Such shifting of the iield therefore causes induced currents in the coil 16, which `in turn produce an audible effect in the telephone receiver, and thus serve to render the passage ofV the electric oscillations manifest.

lt will be observed that llicapparatus illustrated in Fie; l serves the double purpose ot a detector and condenser, thereby obviating the necessity of using any external condenser. By varying the size of the disk and the distance between it and thc coil lo, the capacity of the appa ratos as a condenser may be varied, and, by providing,` an adiustable inducl'iance in thc resoinitor circuit, any repaired tuning mayv be ei'ected.

llt will thus he seen that l have provided a very simple device with few parts and no delicate adjustments, and one which experiment has demonstrated is capable of producina` verv ellicient result-s, and it isithought that the numerous advai'itages of my invention will bc readily appreciated by those skilled in, theart l. ln an electric oscillation detector, the combination with means for producing; a normally stationariT magnetic held, ay conductor of imignet-ic material movable in said field, .means for crmtinuously moving said con-- doctor in said lleid, and means in inductive relation to said iield, forreudoring the pas-- sage of oscillations manifest, said last inentioncd means and said conductor together constitutingv a condenser through which thc oscillations pass,

2. In an electric oscillation detector, thc. combination withmeaiis for producingr a normally .stationary magnetic held, a disk of condiidtinfj` magnetic material rotatable in said held, means for continuously rotating` :said disk, means for conducting the oscillationsy of said disk and means in iiuluctive rc.- lation to said licld for remlerine,r the passage of oscillations manifest, said last mentioned means and said conductor together constitutinr; a condenser through which the oscillations pass.

il. ln an electric oscillation detector, llic combination with means for producing a magnetic held, of a disk of conducting inaguetic material, said disk and licld being rcla.- tivelyv movable, means for conducting the oscillations to said disk, and means for rcudering the passage of oscillations manifest comprising a coil surrounding` said disk, said coil and disk constituting a condenser through which the oscillations pass.

1. .ln an electric oscillation detector, the combination with means for producing a magnetic l'ield, of a conductor of magnetic material in said field, means for reiulering,`

the passage of the oscillations manifest coinprising a coil in inductive relation to said eid, said coil and field being normally stationary witn relation to each other but said coil and held on the one hand and said conductor on Ithe other beineY relatively movable and moans tor conducting thc oscillations through said conductor, said means including a condenser formed by the said coil and conductor themselves.

combined condenser and oscillation detector comprising a disk of magnetic material, means for producing a magnetic field, means for rotating said disk in said field, a stationary said disk, and a dielectric coil and disk.

6. In a magnetic detector, means for producing a magnetic field, a magnetic mass l means for continuously moving the mass constituting one denser, means constituting the said condenser, and means ior conducting the yelectric oscillations through said condenser.

separating said uni 'orm a constant unvarying distortion of said iieldis iroduced, means for subjecting said mass, wlliile rotating, to the influence' oi' electric oscillations and tlius producing a c lia'ngein the distortion ol the field, and'means in inductive relation to, said field for rendering such change manifest.

9. In a magnetic detector, means for 10. -I'n a receiving apparatus for electric oscillations, the combination with an aut0- 'member, and

I'clianges in magnetism 1n said transformer, and aerial and ground wires connected thereto, of means for producin k, a conductor connecting said disk to one point of said a`V stationary coil in proximity and insulated tlierefrom, a conminals of said coil.

11:1-n a magnetic detector for electric oscillations, in combination, a magnetizing member, an tively movable, said magnetizable member being located vin the field created by the magnetizing member, .and means for creating changes in magnetism in the magnetizable member, said means and magnetizable member forming a condenser.

'12. In a magnetic detector rfor electric oscillations, in combination, a magnetizing tively movable,` said ma being located in the ie magnetizing member, and changes in magnetism in d created by conductor, of means for creating a magnetic field, a core of magnetic material, said means and core being relativel movable, means connected to the oscilliation receiving conductor for creating core and a receiving'instrument inductivel aiiected by for receiving osci lations, said second means and core forming through which the oscillations'pass.

In testimony whereof I affix my signature in presence of two witnesses. i

JosEPH MURGAs] Witnesses 1 f JOHN P. PoLLooK, Josnrii L. CAREY.

a magnetizable memberrela-A a magnetizable member rela-` netizable member a condenser 

